Alright, let's work through 2488 times 715 step by step
2488 × 715 = 715 × (2488)
+ 715 × 8 what gives us 5720
+ 715 × 80 what gives us 57200
+ 715 × 400 yielding 286000
+ 715 × 2000 which equals 1430000

= 1778920
